Control apparatus



I $pt'.21 19 65 'M.II NESLIN a 3,207,339: f I

CONTROL APPARATUS Filed Feb. 5, 1962- Y 4 Sheets-Sheet 1 FIG f j L'Awxz22%., 7 BY AT'TO may.

f se t;21,1965 MMESUN" 3,207,339

CONTROL APPARATUS Filed Feb. 5,1952 I I Z1 Sheets-ShetL? ATTORNEY MILAN AMESLIN 4 Sheets-Sheet s INVENTOR. MILAN A. NESLIN Sept. 21,1965 A. NESLIN CONTROL APPARATUS .Filed Feb. 5. 1962 owm.m

n30mU .ujoEzou m 56: 525mm F 3 M. A.1NESLIN 3,207,339 CONTROL APPARATUS J v Q 4 Sheets-Sheet 4 .Fild Feb. 5', 1962 f INVENTOR. MILAN A.NESLIN BY WIALM mQJNI v oz 02.2.5228

ATTORNEY 29, "respectively; may be '7 l The proper point on the ho' t motion v rotated ina standard asdetermined by 'the position of hoist controller 43 and crowd controller 44; respcctivelyr Thefmotor generator sets and regulators are standard "commercial products widely used in shovels. The hoist ,motion.and-crowdrnotion may be controlled independmannerv ently, asihas been therprior practice, by the hoist and crowd controllers, respectively.

The shovel i's set todig automatically by moving switch 5912f automatic regulator 50 from the HAND position m the AUTO.- At some time before-the automatic dig control isactuated, the operato'rexamines the bank and preselects the desired automatic digging speeds. Thet Zauto'matic,diggingspeedslare selected by varying the auto- }"matic reference signal'. The automatic reference signal maybe varied while digging by some conventional means such as-variabl resistance 57'and swi tch 58. The digging I speed 'is. established byloadingof the hoist motion and theilimits of the; hoist motion-shown in FIGURE 1: -'"-Therefore,ithe3operator essentially selects the points" on the graph-of FIGURE- 1 a't which he chooses to dig,auto-' maticall'y by v'arying resistance 57. The automatic dig control isractuated- -by. moving both the hoist and crowd limits curve may controllers to' a specific positionwhieh energizesthe hoist, andcrowdiregulatorsfor. automatic operation.

beydetermined by the individual experience of the operator-or'bycrefererice to "a prepared'ch-artg; The; chart jwouldtake into consideration such tacto'r s as-height of bankrt'ype of fmaterial in bank, consistency of material,

. 'Qshape of th'elbankiand preparation of the bank by drilling; I

blasting or other; means.

"7 {rnay be continuously variable to select-"interniediatepoints lgetweenA,CandD. j r v .deriited-fromthe currentifiowing from hoist generator 47' The comparison between the desired and" actual hoist mot-ion isicontinuou s, causingthe crowd motion to be be changed depending. on how close to the desired hoist motion the actual-hoist motion is,

ign'al may be Iprograinrried to automatically change.

Ariantornatic control such as described will insure that Ithe' -dipper of a shovel will be filledv consistently in the i .srnalles'ta-veragedigging'time over an'opcruting shift.

' 1 neticamplifier 54." .Resistor 70 and capacitor 71 provide'..

. 3 Eor'-;purpose's "of this description, four points on the i hoist iriotioncurii'e; A, .B ,'C and D are shown in FIGURE 1'11}? 1 Reference signal switch 59 may, be switched from HAND-rte AUTOLI P imSAA, c or .D or; variable f resistance 5.7 may-be selected: by. switch 58'." Variableresi'st'ance age vtaken from the terminals of hoist 'motor I f hoist motorcurrent is used as the hoist motion'signal, the hoist H motion signal is-takenas the voltage across the cornmutating and compensating'fields. a

The hoist motion signal in .the' form of the hoist motor voltage with resistors 52 and 53 causes-a current flow through winding 51 of magnetic amplifier 54. The refl erence. signal representingthe desiredlhoist motion is; provided by a voltage source and reference winding .60 i in series with variable resistance 57 which'may be a rheostat. -Rheostat is 'shown with four definite points;

A, B, C and Dfte'co'rrespond with points A,:B, Cand D' i i on the hoist motion curve in'FIGUR-E 1f; For finer ad 3 connected to any point on I justment, switch 58 may be rheostat 57. r

pacitor 62; and winding 61 is for stabilizing.

The output .of magnetic amplifier vel'op ampere-turns proportional to the output of magstabilizing. i

The output voltageot magnetic amplifier 64 produces a'icur're nt through" resistor 72 andiamplidyne winding 73.

Theampcre-turns' of winding 73 oppose the ampere-turns of .Winding 75. The output of arnplidyne7 6 is propor-' tional to' ampereturns of Winding 73.

If the hoist motor voltage is too high, theoutpu't of i magneticamplifier-54 is reduced.- This, in;turn,'reduces w the-output of magnetic amplifier 64, which allowsthe voltage of arnplidyne' 76' toincrease in the dire-ctionfto {I FIGUREfSQtohoist motor 42; This hoist signali'i's a function of the vhoistnmotio'n 'andthe point' on' the hoist) motion: curveiir'i FIGURE 1 where the hoistmotion is 1 ope'rating ifThis hoist motion signal may also be derived e ed, ,or'. the'vo'ltage from the hoist generator. 5 .Reference s'ig'nalfsiwiitch S8.rnay be "connected to a variable rev fsistace Bland is'continuously' variable to provide areferv ence' signal indicating the. desired point onthe hoist motion cu'rvea't which-the,hoist'rnotion'should'operate. in Under! automatic control the desired hoist motion sigg rials-sand theac'tua'l hoist motion signal are com'pared in automatic ,regulator which produces a signal indicating the r'na-gnitude'and polarity of the difference. The difierenc'esignal is applied to'crowd regulator 4 9 to cause the crowdmotion to forceharder, ease up, or maintain" the same forceon the dipper in the bank.

upward through "cause the dipper to enter further into the bank.

Ifhoist mot'orcurr'ent is used; the polarityconnections I are-made such that the output of ma gneticiamplifierjdis increased it the motor current is too high.--

:If motor speed'is used for the'hoi'st motion signal,. a

' voltage: is taken from ai ta'chometer connected onthe hoist rruator-shaft Itspolarity is'taken the same as for motor -terminalvoltag'e.. i

I While thisinvention has been explainedand described with the aid of a'par'ticular embodiment th'ereof,,it will be understood that theinvention is not limited thereby and that many modifications will. occurto thosef'skilled in the are. It is therefore contemplated by the appended claims to'coverall such modifications as fall within the, scope-and "spiritof the inventioml 1 What is claimed'is:

-- ging ope'ration including:

(a) means for sen'ng-the hoist motion o-f the diPPe'r' 1 duringthe digging operation and developing a signa 1 corresponding to the actual hoist motion,

. (b)'..and control means connected to said'sensing means responsive to' variations in the actual hoist motion k 2. Apparatus for automatically controlling the hoistand crOwdmotions of a dipper of a shovel 'duringdi'g'ging -70 operationsincluding:

(a) means for sensing the hoist motion of the dipper during'digging operations and .developing a signal corresponding to the actual hoist motion, a v a (b) means'for producing a reference signal corresponding to a predetermined desired hoist motion,

circuit is shown in F ouRa 'Sstis amplified magnetic amplifier 64." Winding 66 andresis'tor d'e- I :1. Apparatus for automatically controlling the'hoistj I and crowd motions of a dipper 'of'a shovel'during'a digerations including:-

1 andrneans' for generatingasignal'correspondingto l the difference between said actual hoistmotlon slgrial and said reference signal to cause the'crowd mo- .ti'on to-be adjusted so that actual hoist motion corresponds to the predetermined desired hoist motion. 3. Apparatus for automatically controlling the hoist motion'of the dipper of a shovel during a digging operation including:

, (a) means for developing a signal-corresponding to the actual hoist motion,

' g (b) means for producing a reference signal correspondto a predetermined desired hoist'motion;

.(6) means for generating a signal corresponding to the 1 difference between said actual hoist motion signal and said-reference signal tozcause the actual hoist motion jto-beladjust'ed to the predetermined desired hoist mo r (d) and means for changing said reference signal.

-. 4.; Apparatus forautomatically controlling the hoist and I crowd motions of adipper'of a shovel during digging op- (a); means for sensing the hoist motion of the dipper during digging operations and developing a signal corresponding to the actual hoist motion, (b).means for producingareference signal corresponding-to'a predetermined desired hoistm'otio'n;

(c) means-for generating a signal corresponding to the I differenceb'etmen said actual hoist motion signal and ysaid reference 'signalto cause the crowd {motion to be adjustedso thatactual hoist motion corresponds v to the predetermined-desired hoist motion,

- I *f (d)' and-'mea1 is for changing said reference signal. H r d z r 5 Apparatusfifori automatically controlling the hoist and crowd motions of aldipp'er of a shovelduring digging operations'includingi" means for starting the hoist motion of a tdipperof a'sh'ovel,

, jduifingithedigging operation and developing. a signal corresponding to 't-he'.actual hoist,motion,=

aw) man s-for sens'ing m ters: mafia-cr mps (c) means for producing a freference signal correspondq ing'toaipredetermined desiredhoist motion (d) means for generating a 'diifernce signal corresponding to theditference betweensaidactual hoist signal I andsaid reference signal, f

spons'ive to said ditferenc'eksignal for "causing the (e) and means; for 'controllingthe' crowd i motion re- .-cr.owd motion to he. adjusted-so nroti'oncorresponds tothe desired hoist motion. v

6. Apparatus for automatically controlling the hoist and crowd motions of a dipper of a shovel during digging operations including: 7 v v (a) means for starting the hoist motion of a dipper of a'shovel, I} Y (b) means for sensing the hoist motioniof the dipper during the digging operation and developing a signal corresponding to the actual hoist motion,

(c) means for producing a'reference signal corresponding' to a predetermined desired hoist motion,'. (d) means for generating a difference signal corresponding. to the diiference between said actual hoist v signal and said reference signal,

(e) means for controlling the crowdmotion responsive to said-difference signal forcausingthe crowd motion to be adjusted so that the actual hoist motion Primary Examiner. I ERNEST =A. FALLER, HUGO o. SCHULZ, Examiners.

that the actual hoist v (f) and means for varyingsaid reference signal accord:

leonard 31s-56'x 

1. APPARATUS FOR AUTOMATICALLY CONTROLLING THE HOIST AND CROWD MOTIONS OF A DIPPER OF A SHOVEL DURING A DIGGING OPERATION INCLUDING: (A) MEANS FOR SENSING THE HOIST MOTION OF THE DIPPER DURING THE DIGGING OPERATION AND DEVELOPING A SIGNAL CORRESPONDING TO THE ACTUAL HOIST MOTION, (B) AND CONTROL MEAND CONNECTED TO SAID SENSING MEANS RESPONSIVE TO VARIATIONS IN THE ACTUAL HOIST MOTION RELATIVE TO A REFERENCE HOIST MOTION TO CAUSE THE CROWD 